HDD makers have adopted sound power & the dBA scale. You can accept HDD noise specs with some confidence. There is a question of understanding how to interpret sound power figures, but as a comparative scale, it works fine.
A few PSU makers actually provide reasonably good sound pressure (dBA@1M) stats, but most don't.
Fan makers are the worst, in general. The vast majority barely give you 1M readings, and always only without load, so the numbers ALWAYS look lower than in reality. Very misleading, as a result.
Of course, any product whose noise is mainly the fan and inexpensive (HSF), you can bet they NEVER really test them. Question of economics & perceived ROI. The vast majority of component MFGs still don't think there's any real gain in providing accurate noise stats (which will not be cheap if you have a big product lineup and/or one that changes all the time).
A contact at VIA recently lamented the incredible difficulty of trying to get across to case manufacturers for the Mini-ITX platform that noise is an issue, that quieter is better: despite pushing and prodding and direct demands from VIA, the case/psu makers continue to provide less than quiet solutions. It is a continuing challenge for VIA, who is alone among the bigger players in really championing quiet.
The reasoning for that is simple: with owenership of the C3, it is a viable marketing strategy for them. (I don't think you'd see them pushing quiet if the C3 was a hot but powerful monster like the P4s and XPs; they'd be right in there pushing power!)
I've said this all along: the only way that you'll see the industry make a wholesale change is if the market sends a clear (LOUD
) message that taps directly into $$ coffers. That's you and me and anyone who buys PCs & components. As long as people are buying/paying for loud things, they will keep making and selling them.
What can we do? Keep asking for quiet stuff, buy them and don't buy loud stuff, and persuade others to do the same. Esepcially in the corporate scene. Yeah it sounds evangelical. ("Let me in your house & I'll show you why your PC is noisy..."
) Too bad. That's just the way it is. No one else is going to do it.